doc: Indicate possible states when updating a pipeline or a connector

[raulb]

Description of change

Working on https://meroxa.zendesk.com/agent/tickets/121 I realized we don't indicate well the different possible states when updating a pipeline. For connectors update we showed them as part of usage although it also included [FLAGS] right after it so it wasn't entirely right. This pull-request makes that a bit clearer.

Type of change

• New feature
• Bug fix
• Refactor
• Documentation

Demo

Before this pull-request

Usage:
  meroxa pipelines update NAME [flags]

Examples:

meroxa pipeline update old-name --name new-name
meroxa pipeline update pipeline-name --state pause
meroxa pipeline update pipeline-name --metadata '{"key":"value"}'

Flags:
...
      --state string      new pipeline state

After this pull-request

Usage:
  meroxa pipelines update NAME [flags]

Examples:

meroxa pipeline update old-name --name new-name
meroxa pipeline update pipeline-name --state pause
meroxa pipeline update pipeline-name --metadata '{"key":"value"}'
meroxa pipeline update pipeline-name --state restart

Flags:
...
      --state string      new pipeline state (pause | resume | restart)

Additional references

I wonder if those states comma separated would make more sense.

Documentation updated

https://github.com/meroxa/meroxa-docs/pull/46

[lovromazgon]

LGTM